I noticed on shaders where the metallic effect is achieved with a texture, the diffuse output in Cycles is white, eg. full metallic in that case, where else on shaders its black. Of course this is invisible, as its multiples with the color channel, which correct black.
Now this is all invisible, but still wrong, but becomes visible, when ever texture antialiasing is less precise, like with motion blur. In that case the texture borders become white lines around each of these.
Now, there are some other bugs with motion blur, but anyone else getting that, or knows a work around?
better gives some pics showing this effect and nodes set up may be a sample file
then we might be able to help
happy bl
Did you try to use the metallicness texture to mix the principled with another material in the metallic areas?
Anyway, maybe you should make a bug report to help the developers.
Sorry, what version of Blender are you using? I made a test here and the metallic parts here in my test come black on the diffuse map. Using Blender 3.2
Give me some time, i have to do more testings on that. I know i have to be more precise, but my current guess, it had to do with metallnes not being 100 %…